Automobiles are subject to a so-called “greenhouse effect”. This well understood scientific phenomenon results when short wave heat radiation from the sun traverses the glass windows of a vehicle and is absorbed by the material internal to the vehicle. This results in the heating of the passenger portion of the automobile. Also, the glass windows of an automobile are opaque to the longer wave heat radiation emitted from the heated material. As such, the glass acts as a conduit for the heat from the sun to enter the vehicle and as a deterrent for the heat generated by the heating of the material within the vehicle from escaping back out of the glass. As a result, the temperature inside the vehicle will rise to until equilibrium is reached between the heat conducted out through the walls and roof of the vehicle and the amount of heat entering through the windows.
Automobiles are also heated through the conduction of heat through the walls and roof of the automobile. This is due to the fact that the insulation in the roof and walls of typical automobiles is a fraction of what is needed to reduce the inward conduction of heat into the vehicle.
As a result, the temperature of the interior of automobiles that are parked in the sun in hot climates can rise to as much as 150° Fahrenheit. After existing in this condition for a while, not only is the air in the automobile very hot, but all of the material in the interior of the automobile, including the dashboard, seats, armrests, etc., are very hot as well. This heat penetrates to a depth of several inches and reduces the useful life of the interior of the automobile. It can take upwards of twenty (20) minutes for even the best automobile air-conditioner to cool the interior of an automobile to a comfortable temperature.
Several devices have been developed in an attempt to reduce the heat build up in automobiles. For example, tinted glass is used to deflect some of the heat from the sun's rays before it enters in the vehicle. However, due to the limitations by most state transportation departments, it is illegal to tint the windows to a level that adequately reflects the sunlight. Also, the tinted glass does not help insulate the roof or the walls of the vehicle.
Other attempts to combat this problem have resulted in the development of windshield reflectors. For example, U.S. Pat. No. 5,291,934, issued to Ouvrard, et al., U.S. Pat. No. 5,468,040, issued to Peng Hsieh, et al. and U.S. Pat. No. 5,752,560, issued to Cherng discloses power operated sunshades for automobiles comprising extension rods that are placed within the vehicle in an effort to reduce the amount of heat from the sun within the vehicle. All of these prior art patents have drawbacks in that they take up valuable space within the vehicle, are not aesthetically pleasing, and do not adequately reduce all of the heat within a vehicle because they provide no protection for the roof of the vehicle or the side windows of the vehicle.
Other prior art devices have been used in an attempt to reduce the level of heat within a vehicle. For example, several vehicle covers exist which require manual placement over the vehicle in order to block the sunlight from entering the vehicle. A few automated systems exist, including U.S. Pat. No. 4,432,581, issued to Guma and U.S. patent application Publication No. 2002/0033616 A1 issued to Schlecht et al. However, these devices are bulky and cumbersome. These devices also requires numerous adaptations made to the vehicle in order to support the cover.
Thus, it is seen that there is need in the art for an automated covering for a vehicle used to protect the vehicle and block sunlight from entering the vehicle thereby reducing the internal temperature of the vehicle.